Mining drill



y 1952 E. J. HUCKSHOLD 2,595,525

MINING DRILL Filed March 11, 1947 FIG. I.

INVENTOR: 9 5 ,4 4 ELMER J. HUCKSHOLD ATTORNEYS.

Patented May 6, 1952 MINING DRILL Elmer J. Huckshold, St. Louis, Mo., assignor to Central Mine Equipment Company, St. Louis, Mo., a corporation of Missouri Application March 11, 1947, Serial No. 733,816

3 Claims. 1

This invention relates generally to mining drills and particularly to drills of the character utilizing removable bits.

In mining operations which are carried on through non-homogeneous formations, it is frequently desirable to vary the orientation of the cutting edge of the bit with respect to the movement of the drill. The miner knows from experience that, when the cutting edge is arranged to attack at one angle, better progress is made through certain types of formations than when the cutting edge is advanced at another angle.

The object of the present invention, generally stated, is to provide a mining drill wherein the removable bits may be arranged in a variety of orientations with respect to the movement of the drill.

A further object of the invention is to provide a bit-receiving-and-retaining assembly for a mining drill, which will hold the bit in proper position more securely than those heretofore employed and at the same time permit of ready assembly and disassembly.

Other objects will become apparent to those skilled in the art when the following description is read in connection with the accompanying drawings, in which:

Figure 1 is a view in side elevation of a typical mining drill provided with the bit-receiving-andretaining assembly of the present invention;

Figure 2 is an end view of the drill shown in Figure 1;

Figure 3 is a view corresponding to Figure 2, but showing the bits in section flush with the end of the bit-retaining wedge;

Figure 4 is a view in side elevation showing the sub-assembly of bits and bit-retaining wedge;

Figure 5 is an end view of a drill showing a bitreceiving socket of modified form;

Figure 6 is a sectional view taken along line 6-6 of Figure 3; and

Figure 7 is a perspective view of a bit-receiving wedge suitable for use in connection with the drill of Figure 5.

The present invention contemplates that the bit elements of a mining drill be formed of rod stock preferably having a regular polygonal cross section. In order to retain such a bit in active position in the head of a mining drill, the latter is provided with a socket having an interior contour conforming generally to the exterior contour of a cooperating wedge. The contours of the socket and the wedges are preferably conical, but the conical form is departed from in certain regions whereat both the wedge and the socket are recessed to provide in each a space fitting part only of the exterior contour of the bit to be employed. The present invention especially contemplates that such recesses be so formed and proportioned as to fit the bit in more than one orientation. For example, in the case of bits having a square cross section, the socket in the head may be recessed to conform to half of that cross section and the wedge complementarily recessed to conform to the other half of the cross section of the bit. The parts are then additionally recessed to conform to the cross section of the bit when orientated in 45 displacement (about its own axis) from the previously selected orientation. Consequently, with a square bit, the recess will be octocorn. If, on the other hand, the bit is formed of triangular stock, so that the cross section thereof is tricorn, the bit-receiving cavity formed by the complementary recesses in the wedge and the socket will be hexacorn or Star-of-David-shaped.

Referring now to the drawings, the drill head I is provided with a pair of sockets 2, which are conical save for the bit-accommodating recesses provided therein. In the embodiment shown in Figures 1, 2, and 3, each of the sockets 2 is provided with two longitudinally extending recesses 3 and 4, as shown clearly in the lower left quadrant of Figure 3. The recesses 3 and 4, as shown in Figure 3, are adapted to receive bits 5, which, in the embodiment shown, are of square cross section, and such bits are accommodated by the recesses 3 and 4 in a variety of orientations. In the embodiment shown in Figure 3, the recesses 3 and l are so formed as to provide locating corners 6 and l, which will receive and engage the bit when in the position of the bit shown in recess 4 of the upper half of Figure 3.

The recess in the socket is further provided, however, with a corner 8 adapted to receive and engage the bit when in the position shown in the recess 3 of the upper half of Figure 3. A wedge 9 having an exterior contour of generally conical form to fit the interior contour of the sockets 2 is likewise provided with a longitudinally extending recess in its surface. In the embodiment shown in Figures 1, 2, and 3, the wedge 9 is provided with two such recesses l3 and M, respectively, for complementary cooperation with the recesses 3 and. 4 in the sockets 2. The recesses l3 and I4 are formed and proportioned in like manner to recesses 3 and 4, so that the space defined by the complementary recesses corresponds to the exterior contour of the bit in the several positions of orientation.

While the recesses l3 and H! are open at the outer, i. e., the larger, end of the wedge 9, the inner ends thereof are closed, as shown at 15, in order to provide a seat for engaging the inactive end of the bits 5.

In the embodiment shown in Figure 5, the socket 2 is provided with four recesses 3, 4, 30, and 40 of the character above described. These recesses are located in 90 displacement about the interior of the socket 2. By utilizing a wedge 19 of the character shown in Figure 7, which has but one bit-accommodating recess [3 but is otherwise identical in all respects with the wedge 9 hereinbefore described, a single bit may be positioned in the drill head of Figure 5 in either of the four recesses 3, 4, 30, and 40, and in either of the several orientations in each of such recesses.

From the foregoing description, those skilled in the art should readily understand that the invention accomplishes its objects and increases the versatility, and consequently the efiiciency, of the mining drill.

While, in the embodiment shown in the drawings, the bits utilized are formed of square stock so that the complemental bit-receiving recesses are eight-cornered, it is to be distinctly understood that the invention is not limited to an eight-cornered recess for a four-cornered bit, but, in fact, the bit-accommodating recess may have any multiple of four number of corners. Likewise with bits of other regular polygonal shapes, such as triangular or hexagonal, the complemental bit-receiving recesses of the socket and wedge may have such number of corners as respectively constitutes a multiple of three or a multiple of six. It is, therefore, to be distinctly understood that the invention is not limited to the details of the foregoing disclosure save as indicated by the appended claims.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:

1. In a mining drill, a head having a tapered socket therein with a larger cross sectional portion at the free end of the head, said head having a recess in the socket extending lengthwise thereof with a transverse cross section presenting more than two symmetrically spaced corners, a tapered wedge fitting within said socket, said wedge having a longitudinally extending recess therein with a transverse cross section presenting more than two symmetrically spaced corners, the recess in said wedge being disposed in a position complementary with the recess in the socket providing a cavity for receiving a bit having a polygonal cross section, said corners in both of the recesses being twice as many as the number of corners on the bit so that the bit may be arranged in the cavity in a plurality of orienta- 6 tions differing by less than the angle between faces on the polygonal shaped bit whereby a cutting portion of the bit may be adjusted with respect to the direction of rotation of the drill.

2. In a mining drill, a head having a socket therein, a frusto-conical wall defining said socket with the larger diameter portion thereof at the free end of the head, said wall having a recess therein extending lengthwise of the socket with a transverse cross section thereof presenting more than two symmetrically spaced corners, a wedge having an exterior frusto-conical surface fitting within said socket, said surface of the wedge having a longitudinally extending recess therein with a transverse cross section presenting more than two symmetrically spaced corners, the recess in said wedge being disposed in a position radially aligned with the recess in the socket wall providing a cavity for receiving a bit having a polygonal cross section, said corners in both of the recesses being twice as many as the number of corners on the bit so that the bit may have a plurality of orientations in said cavity differing by less than the angle between faces on the polygonal shaped bit whereby a cutting edge of the bit may be adjusted with respect to the direction of rotation of the drill.

3. In a mining machine having a removable bit, a head having a socket therein, a frustoconical wall defining said socket with the larger diameter portion thereof adjacent the free end of the head, said wall having a plurality of recesses therein extending lengthwise of the socket, each of said recesses having a transverse cross section presenting more than two symmetrically spaced corners, a wedge having an exterior frusto-conical surface fitting within said socket, said surface of the wedge having a sole longitudinally extending recess therein with a transverse cross section presenting more than two symmetrically spaced corners, said wedge being rotatable to position the sole recess therein complementary to any one of the recesses in the socket wall to provide a cavity for receiving a bit having a polygonal cross section, said corners in both of the complementary recesses being twice as many as the number of corners on the bit so that the bit may have a plurality of orientations in said cavity differing by less than the angle between faces of the polygonal bit.

ELMER J. HUCKSHOLD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

